by PHILIP J. MESSENGER
Equipment & Tools
Because aircraft have so many difficult areas to inspect and clean, specialized equipment and tools are necessary to assure a FOD free product. Some manufacturers rotate or shake the entire aircraft assembly at various stages to dislodge foreign objects but a flashlight and mirror can only go so far. Specialized equipment is necessary to verify cleanliness. One of the most valuable tools to inspect and retrieve FOD is the borescope. This tool was originally developed to inspect within the human body but is now used in many industrial applications to perform inspections that otherwise would not be possible without dis-assembly or destruction. Numerous companies build borescopes that are ideal for aircraft inspection and cleaning. A wide variety of borescopes are available with specialized uses; some are designed for engine inspection, some have articulating tips with FOD retrieval capability and some are ideal for fuel cell inspection with explosion-proof lighting units.
It is important to consider the safety aspects of the area to be inspected before deciding on the borescope to be used. Never use a borescope on electrically powered circuits. It is recommended that aircraft batteries be disconnected if there is any chance of electrical contact or shorting. Not only can aircraft components and the borescope be damaged, personal injury to the borescope operator is possible. Limit the use of borescopes to those persons trained in the operation, maintenance and safety characteristics of the equipment. Borescopes are expensive and fragile; improper care or use can easily damage or destroy this valuable tool. It is recommended that borescopes be used only by the FOD Department personnel, who should keep the equipment under lock and key when not in use.
It is one thing to locate FOD, it’s quite another to remove it. Ingenuity is often required. Sometimes FOD cannot be removed and must be secured with sealant to assure it will not migrate or get loose. Long extension tubing can be affixed to a sealant gun to perform this operation.
Other FOD inspection/removal tools needed include: pneumatic powered vacuum cleaners with extension suction tubes, mirrors, high intensity lights, magnets and a variety of “FOD grabbers.”
Within the manufacturing environment, FOD controls vary with the type of work being performed. Three distinct categories of operation are evident: Fabrication, Assembly and Checkout/Test. Although all share the same key elements of control, each category differs enough to allow diversity within the control methods. Rules that apply to the flightline may not be practical in a backshop. For supervisors and workers to support the FOD Program, they need to understand the importance of the controls and acknowledge that they are reasonable given the work at hand.
Often called “backshops,” these are work areas such as sheetmetal, machine shop, tubing and electrical harness. Typically, these shops do not have enclosed panels or components; therefore, FOD control is less critical than in other manufacturing areas.
These are areas where fabricated parts are put together and cavities are enclosed with fasteners or sealant. These areas require greater control and more frequent inspections and cleaning than Fabrication areas. All areas or panels “closed out” should have a FOD buyoff (inspection) on the paperwork (documentation of process).
This requires the highest level of control because the product is in its final stages preceding delivery or flight. Assurances must be made that all personnel entering the work control area remove all loose/unsecured personal items, e.g., watches, keys, jewelry and coins, and account for all tools and hardware carried near the product. A tool/ hardware inventory form may be required in certain FOD-critical products or areas.
It is important to clearly define the control areas so there is no question about which rules apply. Also, keep in mind that work “travels” when not completed in its designated area. For example, a component not completed or available in assembly must be installed in checkout/test. Typically, the worker who normally installs the component in assembly is the one who “travels” to checkout/test to install the part. Therefore, it is critical that all workers who may function in another control area be familiar with the FOD control requirements for any area in which they may work. Training, SOPs, signs and supervisors of each process must learn and support the differing rules for each control area.
The key elements of FOD Prevention are universally accepted but applied in various ways throughout the aerospace industry. To cooperate with the control areas addressed above, each element must be dissected and articulately defined to allow clarity and ease of enforcement. The better defined, the better understood. The better understood, the better compliance. Posters and other visual reminders should be used to promote the rules. Everyone working at the facility should know and understand the key elements… including security personnel. You know your FOD Awareness Program is working when a washer is retrieved from the shop floor and reported by an administrative clerk! The key elements are something to advertise. Don’t keep them hidden in a procedure folder or meeting room. Plaster them on the walls, publish info bits in the company newsletter or on the intranet, make up or purchase FOD stickers to put on tool boxes and work benches, have poster contests, give recognition awards for compliance and do anything else you can think of to keep people focused. The monthly emails produced by FODProgram.com are specifically written to keep this awareness high.
The key elements are easy to remember because they are so integrated within the manufacturing workplaces: Tool Control, Hardware Control, Product Protection and “Clean-As-You-Go.” Keeping the rules simple is important. So is defining their specific applications, as you can see from the following Chart.
Letter Codes for the three control areas are:
F = Fabrication
A = Assembly
C = Checkout
Want to learn more? Contact us for guidance on developing your FOD prevention program.